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Working on some Compaq portables - tips/tricks?

So I have 2 projects currently going. 5 years ago a friend gave me a Compaq portable III he had, and I powered it on, it needed a boot disk, and in my basement it went for 5 years. I've decided to dig it out, and have setup my 98/XP machine with a 5.25" drive so I can now make boot disks for it, and have started booting it up and seeing what it can do. It powers on and boots, so that's a good start.

So now I'm hoping to do a little fixing up. It doesn't have an internal HD (or at least it doesn't have a working internal HD). I've read this link - https://rclassiccomputers.com/2017/08/08/portableiii/ - and it has good tips for the battery (not sure I'm clear about scraping holes and am worried about damaging things trying that, so.....better pictures might be good for that? Or a video? If such a thing is out there....but I can work without a battery for now) and for setting up an SD card as an HD.

Also, I've noticed some graphics limitations on this model. I tried running the Compaq demos on a Compaq DOS disk. It fails to show the Compaq logo on the top of the menu, just a floating R that I think would have been in the upper right corner of the logo that they used text to do, and when trying to run things like space spiders or musical art, nothing displays on the screen. It's unable to draw things. It is running the programs, in the case of musical art, the text displays on the first screen, and the sounds work. But from what I've seen from articles on this machine, it appears it should have those capabilities to draw.

coolstuff4819.blogspot.com
My COMPAQ PORTABLE III 286 PC!
I'm typing this in WordPerfect 5.1, from 1989, on my Compaq Portable III PC, which I got a few days ago from the place I worked over the sum...
coolstuff4819.blogspot.com coolstuff4819.blogspot.com

I can't seem to find if there's an add on or accessory that makes that possible. Or if there's just something wrong with mine.

I don't have access to a CGA monitor at the moment, but am hoping to track one down soon, so I can test the CGA output on it and see if that makes a difference.

Also, it has 640k of RAM, which I suppose is good enough to play around some, but I know it had the ability to hold more RAM....but I don't even know what I'm looking for as far as RAM chips for a Compaq portable.

So I guess any suggestions on that would be appreciated.....more tips on the battery issue (I'm not that great at doing delicate work that has the risk of destroying things), the graphics issue, and whatever other things I should check out on it.

Project 2 is that I finally tracked down an original Compaq portable. When flipping the switch, the fan hums to life. But that's about it. After opening it and reseating cards, I did get it to beep once and then the light for the 5.25" drive came on. No display on the screen. Never gave up and turned out the light. I tried again now that I have a boot disk, but now I can't get it to beep and turn on the light, just turns on the fan. I don't even know where to begin with something like this. My normal methods of troubleshooting on modern stuff would involve swapping out parts with known working parts.....but I don't have access to spare Compaq portable motherboards and cards. I watched a video on youtube about a Compaq portable restoration, and while it was fun to watch, all that left me with is that it's helpful to have friends that just happen to have working parts hanging around that they can give you. So.....yeah.....not sure how to go about starting to get that to work, but I intend to have a fully working Compaq Portable one way or another. Suggestions?

Ok, cool. One is on it's way, and that should get me on my way to furthering the work on the Portable III.

Meanwhile, on the Portable, I got it opened, and determined it was a power issue. Even with all cards out, and all drives disconnected, I found that the red light on the mobo would only blink briefly when turning on the power supply. I got to the power connector to the mobo, and took some measurements, and I don't know what is supposed to read what, but nothing read at 12, but some read at 2.5 or -2.5. I think it's safe to say the power supply needs work.

I took the cover off of the area covering the screen and power supply to take a look. There is a bunch of white gunk around some of the components, not sure if that's adhesive to hold things in place, or residue from something going bad. Anyways....at that point, it was late, and I put it back together for now. I'm not sure how to get further into it and get the power supply out of there, and I also don't have much in the way of info or schematics, I'm just digging in and looking around really.

What's the next step on this? Could someone point me to schematics or more detailed information? Any pictures/video out there of power supply work being done on these? I think if I could get the board out of the case, I probably could handle a few capacitor replacements.

My apologies if this is a repeat post, I think I accidentally clicked on an X that deletes the post while pending approval.

Thanks for the advice on the Portable III, I've ordered a module and will work on that.

Meanwhile, back over on the Portable, I got a bit further. I dug in and determined that the mobo wasn't getting power. I measured the contacts off the power supply and found values that I believe are low. Nothing measures at 12. I took the cover off the monitor/power supply area, and found some components covered in white residue, not sure if that's adhesive, or residue from something gone wrong. At that point it was late and I put it back together.

I could use some schematics for this if they are available anywhere, and if anyone has any experience working on the power supply on a portable, advice would be appreciated, I'm not sure how to get the board out of there. If I can get the board out and get my hands on some schematics, and specifications on what the pins are supposed to read, I should be able to handle replacing a few capacitors and getting the power supply back to working order.

Geeze, not much in the way of interaction around here, is there. Not much for help around these parts.

I did get a DOM on the Portable III. Not really a great option though, there's not much for clearance on the port on the motherboard, I had to buy an IDE extender cable to act as an IDE cable so I could install the DOM in a place where there's more space to hold it. But now I'm finding that when getting into the hardware setup, you have to select a specific disk type, and a 16GB modern module isn't exactly a HD type that Compaq was anticipating in the 80s. Am I stuck? How do I get this machine to recognize this module?

The system settings require a disk type number.....NONE THAT ARE COMPATIBLE WITH THE DOM!!!!

Heck, on a more modern machine, I have the module connected, trying to do a DOS 5.0 install (which is a reasonable OS to use on a Compaq Portable III), FDISK DOESN'T SEE THE MODULE AT ALL!!!

COMPLETELY INCOMPATIBLE!!!!!

AWFUL SUGGESTION!!!

Anyone around here that knows how to work on these machines that could offer any useful advice?

This forum so far has been pretty useless......I can't even post anything without it taking days to show up, and then no one around here seems to want to respond, or make a few vague suggestions that are completely off.

Well, I managed to get windows on it...
I'd show a picture.....but the forum said it exceeds the file size, so no picture for you!

Managed to get the 40MB hard drive to work. Not sure for how long though, but it seems to be the only option since I can find no way to select a type that will work with any modern device, and no one around here seems to be able to offer much in the way of information as to how it could be done....